Venous access to a patient's venous system may be accomplished using a peripheral intravenous catheter (PIC) in some instances and a central venous catheter (CVC) in other instances, which are well known in the health care industry. For long term venous access, a subcutaneous implantable port (sometimes referred to only as “port”) is preferred. An implantable port generally comprises an injection port housing, typically made from an exotic metal such as titanium, and a catheter implanted under the skin with a catheter connected.
To access a patient's venous system, a Huber needle is typically used to puncture through the injection port housing, and obviously through the skin. Once completed, the injection port housing reseals itself. It is not uncommon to be able to access the injection port housing hundreds of times before having to replace it. It is also not uncommon to leave a Huber needle in the injection port housing for extended time periods, in the order of several days, without increased complications. However, the longer the needle remains in the port, the more difficult it is to remove. It is well documented that this resistance to removal causes a rebound affect when the needle is withdrawn from the port thus resulting in possible needle sticks to the clinician. In addition, the rigid needle remains in a layer of tissue directly above the port resulting in discomfort to the patient.
More recently, the use of a polymer, such as a polyurethane catheter, to access the injection port housing is preferred as it increases the intervals between having to remove the device from the injection port housing, and hence the number of punctures through the same housing for venous access. It would be desirable to use a plastic catheter over a needle for port access. That way, the needle can be withdrawn immediately after insertion leaving only the plastic catheter in place. The flexible (or semi-rigid) catheter would provide more comfort to the patient and be easier to remove. It would also be desirable to provide a safety shield to protect the needle point after removal to prevent inadvertent sticks.